//
//  UIImage+CutImage.m
//  SelectPhotoForCamera
//
//  Created by 李忠 on 2016/11/4.
//  Copyright © 2016年 tynDog. All rights reserved.
//

#import "UIImage+CutImage.h"

@implementation UIImage (CutImage)

//按照指定宽度缩放图片
- (UIImage *)compressImage:(UIImage *)sourceImage toTargetWidth:(CGFloat)targetWidth {
    CGSize imageSize = sourceImage.size;
    
    CGFloat width = imageSize.width;
    CGFloat height = imageSize.height;
    
    CGFloat targetHeight = (targetWidth / width) * height;
    
    UIGraphicsBeginImageContext(CGSizeMake(targetWidth, targetHeight));
    [sourceImage drawInRect:CGRectMake(0, 0, targetWidth, targetHeight)];
    
    UIImage *newImage = UIGraphicsGetImageFromCurrentImageContext();
    UIGraphicsEndImageContext();
    
    return newImage;
}
#pragma mark 裁剪照片
- (UIImage *)scaleToSize:(UIImage *)image size:(CGSize)size
{
    //创建一个bitmap的context
    //并把他设置成当前的context
    UIGraphicsBeginImageContext(size);
    //绘制图片的大小
    [image drawInRect:CGRectMake(0, 0, size.width, size.height)];
    //从当前context中创建一个改变大小后的图片
    UIImage *endImage=UIGraphicsGetImageFromCurrentImageContext();
    
    UIGraphicsEndImageContext();
    return endImage;
}
//做圆形
+ (UIImage *)cycleImage:(NSString *)name{
    
    //1.加载原图
    UIImage *oldImage = [UIImage imageNamed:name];
    // 2.开启上下文
    UIGraphicsBeginImageContextWithOptions(oldImage.size, NO, 3.0);
    
    // 3.取得当前的上下文
    CGContextRef ctx = UIGraphicsGetCurrentContext();
    
    // 4.画圆
    CGRect circleRect = CGRectMake(0, 0, oldImage.size.width, oldImage.size.height);
    CGContextAddEllipseInRect(ctx, circleRect);
    
    // 5.按照当前的路径形状(圆形)裁剪, 超出这个形状以外的内容都不显示
    CGContextClip(ctx);
    
    // 6.画图
    [oldImage drawInRect:circleRect];
    
    // 7.取图
    UIImage *newImage = UIGraphicsGetImageFromCurrentImageContext();
    
    // 8.结束
    UIGraphicsEndImageContext();
    
    return newImage;
}

//name:图片名 borderWidth:圆环宽度 borderColor:圆环颜色
- (UIImage *)cicleImageWithImage:(NSString *)name borderWidth:(CGFloat )borderWidth borderColor:(UIColor *)borderColor{
    
    // 1.加载原图
    UIImage *oldImage = [UIImage imageNamed:name];
    
    // 2.开启上下文
    CGFloat imageW = oldImage.size.width + 22 * borderWidth;
    CGFloat imageH = oldImage.size.height + 22 * borderWidth;
    CGSize imageSize = CGSizeMake(imageW, imageH);
    UIGraphicsBeginImageContextWithOptions(imageSize, NO, 0.0);
    
    // 3.取得当前的上下文
    CGContextRef ctx = UIGraphicsGetCurrentContext();
    
    // 4.画边框(大圆)
    [borderColor set];
    CGFloat bigRadius = imageW * 0.5; // 大圆半径
    CGFloat centerX = bigRadius; // 圆心
    CGFloat centerY = bigRadius;
    CGContextAddArc(ctx, centerX, centerY, bigRadius, 0, M_PI * 2, 0);
    CGContextFillPath(ctx); // 画圆
    
    // 5.小圆
    CGFloat smallRadius = bigRadius - borderWidth;
    CGContextAddArc(ctx, centerX, centerY, smallRadius, 0, M_PI * 2, 0);
    // 裁剪(后面画的东西才会受裁剪的影响)
    CGContextClip(ctx);
    
    // 6.画图
    [oldImage drawInRect:CGRectMake(borderWidth, borderWidth, oldImage.size.width, oldImage.size.height)];
    
    // 7.取图
    UIImage *newImage = UIGraphicsGetImageFromCurrentImageContext();
    
    // 8.结束上下文
    UIGraphicsEndImageContext();
    
    return newImage;
}

@end
